1. Field of the Invention
The present invention relates to a movable pouring basin for use in connection with dispensing molten materials including metals and castable plastic from a vessel into casting cavities moving beneath the vessel. The movable pouring basin has particular utility in connection with metal casting in vertically parted green-sand molds, and when used in connection with a "Disamatic" or "Koyo-type" automatic molding machine.
A description of the Disamatic machine may be found in U.S. Pat. No. 4,749,019 to Sorrell et al., the entire disclosure of which is incorporated herein by reference.
2. Description of Related Information
Mass manufacturing of cast parts may be accomplished by releasing molten casting material into a mold line disposed on a pouring table that "indexes" beneath the casting material source. The mold line comprises a series of casting cavities, each having a passage known as the "downsprue" through which the casting material is introduced into the cavity.
In a typical arrangement, the molten casting material is held in a vessel disposed above the mold line. The vessel comprises an effluent spout which may be alternately opened or closed using a stopper rod. As the pouring table aligns the downsprue of each casting cavity beneath the spout, the pouring table pauses, the stopper rod is lifted, and molten casting material is dispensed. When the mold is full, the stopper rod is lowered to stop the release of casting material, and the pouring table indexes to the next casting cavity. The position of the vessel or spout may be adjustable to facilitate alignment of the spout and a given downsprue.
In lieu of the automated pouring process, the casting cavities can be filled by other means including, for example, the use of a manual, semi-automatic, or automatic tilt ladle. The casting process may also be adapted to cooperate with the well-known Disamatic machine, in that the casting material source and pouring table may be timed to operate at a cycling rate that corresponds to that of the Disamatic machine.
The Disamatic machine produces molds of the "door and ram" type. These molds have two embossed surfaces, i.e., a front surface and a rear surface. The front embossed surface, referred to as the "door half," embodies one-half of a casting cavity and one half of the associated downsprue. The rear embossed surface, referred to as the "ram half," embodies the second half of a cavity and downsprue.
In the mold line, the door half of a first mold will abut the ram half of a second mold to form a complete cavity and downsprue. The respective door halves and ram halves of the molds formed in this manner do not function as separate and distinct molds because any given door or ram half can only create a cavity and downsprue in cooperation with an adjacent door or ram half.
Regardless of the casting system employed, it is undesirable for molten casting material which is being poured into the downsprue of the mold to be splashed, overflowed, or inadvertently introduced into an adjacent mold. Among other adverse effects, this can lead to quality control problems when the splashed or overflowed casting material cools on top of the molds or cools prematurely in an adjacent mold cavity.
In order to reduce these effects, foundries typically have employed a downsprue that is characterized by a funnel-type pouring basin located at the top of the mold (the "integral funnel") in order to provide a reasonably large target for the falling molten casting material. However, the integral funnel limits the size of the casting that can be made for given mold dimensions. In addition, the integral funnel must be filled with molten casting material in order to generate a sufficient head pressure to completely fill the casting cavity, resulting in wasted material which must be remelted before reuse. Thus, the use of integral funnels increases the amount of casting material required to make a given number of finished castings.
A need exists, therefore, for a simple, robust and inexpensive device that can reduce the adverse effects of splashing and overfill as does the integral funnel, but that increases yield by reducing the amount of waste metal associated with each casting.